Surgeons operating in confined regions of a patient's body, e.g., in an ear, throat or vagina, often encounter difficulty in obtaining adequate, clear, safe lighting of the operational site—especially during prolonged operational procedures. This is also the case when surgery is performed in other confined regions such as the mouth, abdomen or pelvis. The mounting of a light source on a surgeon's forehead, light sources manipulated by an assistant, and other known solutions generally are not satisfactory—especially where avoidance of shadowing and correct angle of incidence are important considerations. Neither is the provision of a light source mounted to the surgeon's wrist or finger, or even on the surgical tool itself, if the lighting elements are bulky or if either the lighting or electrical power is conveyed by trailing fiber-optic cables, wires or other arrangements that tend to limit the surgeon's freedom of movement or might become entangled where multiple light sources are required. Furthermore, the provision of clear white light of sufficient intensity for periods exceeding more than a few minutes poses the problem that portions of the lighting system may attain unacceptably high local temperatures and may accidentally cause tissue damage to either the patient or to members of the surgical team. Another concern always present if oxygen is being supplied to the patient is the danger of igniting materials contacted by the hot light source. There is therefore a clearly felt need for a lightweight, compact, readily adaptable lighting system to facilitate safe, satisfactory lighting for surgeons.
Factors that must be considered in developing an answer to this need include affordability both initial and in the long term (i.e., the retail price of any lighting system and the feasibility of sterilization and reuse of at least some of the components, inclusion of rechargeable power sources, etc.), versatility of the solution (i.e., its adaptability for use with a wide variety of known or existing surgical tools), its reliability and its acceptability to prospective users.
The most relevant art is believed to be U.S. Pat. No. 6,428,180, to Karram et al., titled “Surgical Illumination Device and Method of Use”, which teaches a compact, self-powered, selectively-mountable lighting unit that meets many but not all of the requirements reviewed above, e.g., it does not include specific means to deliberately transfer heat away from the light-generating element during operation of the unit. One example of how to conduct away heat from a relatively high-temperature zone in a lighting device is suggested in U.S. Pat. No. 6,834,977 to Suehiro et al., titled “Light Emitting Device”, in which a plurality of LED elements are operated on a common lead from which heat is conducted to another common lead on an opposite side of a substrate. The use of filters in an overhead lighting system, to selectively permit transmission of visible light while impeding transmission of heat energy radiation, i.e., long wavelengths, is suggested in U.S. Pat. No. 6,443,596, to Bulko et al., titled “Surgical Light Apparatus With Improved Cooling”. U.S. Pat. No. 6,675,483, to Bond et al., titled “Combination Barbecue Tool”, teaches a combination tool in which by the use of locking means a single handle may be selectively attached to any of a variety of implements.
It is considered that these and other such references do not, even when considered together, teach how to fully address the problem solved by the present invention as described below with reference to the attached drawings.